Question 1

Which of the following best describes the biological species concept?

Accepted Answer

A species is a group of populations whose members can interbreed in nature and produce viable, fertile offspring.

Question 2

Which of the following is an example of a prezygotic barrier?

Accepted Answer

Habitat isolation

Question 3

Two species of frogs live in the same pond but breed at different times of the year. What type of reproductive isolation is this?

Accepted Answer

Temporal isolation

Question 4

Which of the following scenarios best illustrates mechanical isolation?

Accepted Answer

Two species of snails have shells that spiral in opposite directions, preventing mating.

Question 5

A mule is the sterile offspring of a horse and a donkey. Which postzygotic barrier does this represent?

Accepted Answer

Reduced hybrid fertility

Question 6

Which equation best represents the concept of gene flow between populations?

Accepted Answer

$$p' = (1 - m)p + m p_m$$

Question 7

Which of the following is NOT a limitation of the biological species concept?

Accepted Answer

It cannot account for gene flow between populations.

Question 8

Allopatric speciation requires which of the following conditions?

Accepted Answer

Populations must be separated by a physical barrier, interrupting gene flow.

Question 9

Which of the following is an example of behavioral isolation?

Accepted Answer

Two species of crickets have different mating calls.

Question 10

Which of the following best explains why gene flow can prevent speciation?

Accepted Answer

Gene flow reduces genetic differences, maintaining a single species.

Question 11

Which species concept would be most useful for classifying fossils?

Accepted Answer

Morphological species concept

Question 12

Which of the following is a postzygotic barrier?

Accepted Answer

Reduced hybrid viability

Question 13

In sympatric speciation, which of the following is true?

Accepted Answer

Speciation occurs without geographic separation.

Question 14

Which of the following is an example of gametic isolation?

Accepted Answer

Sperm of one sea urchin species cannot fertilize eggs of another species.

Question 15

Which of the following best describes hybrid breakdown?

Accepted Answer

Hybrid offspring are viable and fertile, but their descendants are feeble or sterile.

Question 16

Which of the following is a real-world example of temporal isolation?

Accepted Answer

Spotted skunks in the east breed in late winter, while those in the west breed in late summer.

Question 17

Which of the following equations could be used to model the probability of hybrid viability given two alleles $$A$$ and $$a$$ from different species?

Accepted Answer

$$P_{viability} = p_A p_a$$

Question 18

Which of the following is true regarding ecological species concept?

Accepted Answer

It defines species based on their ecological niche.

Question 19

If two populations of the same species are separated by a mountain range and cannot interbreed, what process is most likely occurring?

Accepted Answer

Allopatric speciation

Question 20

Which of the following is a consequence of reduced hybrid viability?

Accepted Answer

Hybrid offspring fail to develop properly and die before reaching reproductive age.

Ch. 22 The Origin of Species: Biological Species Concept and Speciation

Study Guide - Practice Questions